/*
 	Tool for Path Finding Algorithm Testing (ToPFAT) 
 	
    Copyright (C) 2009, Teemu Turunen and Arttu Viljakainen 
    Published under GNU General Public License V3 
    (see http://www.gnu.org/licenses/licenses.html)
    
    This file is part of Tool for Path Finding Algorithm Testing.

    Tool for Path Finding Algorithm Testing is free software: you can 
    redistribute it and/or modify it under the terms of the GNU General 
    Public License as published by the Free Software Foundation, 
    either version 3 of the License, or (at your option) any later version.

    Tool for Path Finding Algorithm Testing is distributed in the hope that it
    will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General 
    Public License for more details.

    You should have received a copy of the GNU General Public License
    along with Tool for Path Finding Algorithm Testing. If not, see         <http://www.gnu.org/licenses/>.
 */

package algorithms.astar.heuristics;

import algorithms.astar.AStarCost;
import algorithms.astar.Node;

/**
 * ManhattanDistance heuristic implementation.
 * See A* tutorials for more information.
 * 
 * @author teturun
 *
 */
public class ManhattanDistance implements HCostHeuristic {

	public int calculateCost(Node start, Node goal) {
		int distanceX = Math.abs(start.getLocation().x - goal.getLocation().x);
		int distanceY = Math.abs(start.getLocation().y - goal.getLocation().y);

		return AStarCost.NORMAL_MOVE * (distanceX + distanceY);
	}
	
	public String toString() {
		return "Manhattan distance";
	}
	
}
